Conventionally, every time sheet rolls are formed in a sheet winder, they are hoisted together with their cores by a crane operated by the operator to be brought in this state to a take-up shaft withdrawal position, in which the take-up shaft is withdrawn from the sheet rolls. New cores for taking up sheets are subsequently mounted on the withdrawn take-up shaft, and in this state the take-up shaft is mounted again in the sheet winder.
Recently, large-diameter and heavy-weight sheet rolls are formed on sheet winder take-up shafts. Where such a large sheet roll is taken out of the sheet winder by hoisting it with a crane, it is liable to swing unstably.
In another aspect, in case of a sheet winder with a sheet slitter where slit sheets are taken up in upper and lower groups, the sheet rolls in the two groups cannot be taken out of the sheet winder at the same time.
Further, after the sheet rolls have been taken out, a plurality of new cores are mounted one after another on the take-up shaft, or two take-up shafts are set parallel for the take-up of new sheets. In either case, considerable time and labor are required, and during this operation the take-up operation is interrupted, reducing productivity.